In recent years, technology concerning semiconductor laser light source has improved significantly, and in near future, not only LEDs (Light Emitting Diode) but also LDs (Laser Diode) emit lights in three colors (red, green, and blue), and are expected to be applied to displays and the like. The features of the light output (emitted) from such LD have advantages in high conversion efficiency from electricity to light and high coherency but have disadvantages in high NA (Numerical Aperture) of light output and large expanding angle, thus being difficult to be used.